Lock decoder



Oct. 11, 1955 A. H. HARWELL LOCK DECODER Filed 061.. 27, 1952 3 Sheets-Sheet l INVENTOR frl hur ZZOYarWeZZ ATTORNEY Oct. 11, 1955 V A. H. HARWELL LOCK DECODER 3 Sheets-Sheet 2 Filed Oct. 27, 1952 INVENTOR :i V Jay 22 51% rwsZZ y W ATTORNEY Oct. 11, 1955 H. HARWELL 2,720,032

LOCK DECODER Filed Oct. 27, 1952 3 Sheets-Sheet S m INVENTOR firfhu rHHarweZZ United States Patent LQCK DECODER Arthur H. Harwell, Houston, Tex. Application October 27,1952, Serial No; 316,976

6 Claims. (Cl. 33-174) This invention relatesto a lock decoder of extremely simple construction which may be readily utilized for decoding a lock of the pin and tumbler typehaving a revolving core or plug and which will efficiently function i for accurately indicating the coding of the plug pins to enable a key to be cut which willfit the lock.

Many locks of the aforedescribed character, especially those primarily intended for use as locks for vehicle ignitions and vehicle closures, are no longer numbered or otherwise inscribed with identifying indicia. whereby a decoder which is so constructed that accurate readings i may be obtainedeven on old locks where the core or plug pins are badlyworn.

Still a further object of the invention is toprovide a i lock decoder including a spacing bar having associated graduations for definitely indicating a specific pin being decoded.

A furtherobject of the inventionis to provide a lock decoder having a novel dial meanswhich is automatically actuated by movementof the pin engagingel'ement of the decoderfor indicating the depthreading of the pin engaged by said element. i 3

Various other objects and advantages of theiuvention will hereinafter become mordfully apparent from the following description of the drawings, illustratingrpresently preferred embodiments thereof, and wherein:

Figure 1 is afront elevational view, partlyin section showing one embodiment of the decoder in an operative position; 7 Figure 2 is a rear elevational View thereof; Figure 3 is a horizontal sectional view taken substanure 1 with the handle member omitted;

Figure 4 is a vertical sectional'view taken substantially along a plane as indicated by the line-4 4 of Figure 1;

Figure 5 is a front elevational View of the body portion of the decoder with theother parts removed;

tially along a plane as indicated by the line 3-3 of Fig- Figure dis a fragmentary longitudinal vertical sectional view taken substantially along a plane as indicated by the line 66 of Figure 4;

Figure 7 is enlarged fragmentary sideelevational view of the forward end of the decoderlooklng toward the same side thereof as seen in Figure 1; r a

Figure 8 is a side elevational View of the forward part "of thedecoder looking toward the opposite side thereof,

as seen in Figure 2, and on an enlarged scale;

front and rear walls 15 and 16 project.

Figure 9 is a front elevational view, partly in section, similar to Figure l, of another form of the decoder; Figure 10 is a rear elevational view thereof, and Figure 11 is a cross sectional view taken substantially along a plane as indicated by the line 1111 of Figure 9. Referring more specifically to the drawings and first with reference to Figures 1 to 8, the lock decoder as illustrated therein, and designated generally 12, includes a body member, designated generally 13, which is best illustrated in Figure 5. The body member 13 is preferably formed of sheet metal and is preferably of one piece construction and includes a side wall 14 having outturned flanges at the ends thereof forming a front wall 15 and a rear wall 16. The body member 13 is open at the side thereof opposite the side wall 14. Said body member 13 is elongated beneath the front and rear walls 15 and 16 and is provided with an inwardly turned back fold 17 one end of which is disposed beneath the front wall 15 and the other end of which projects rearwardly beyond the rear wall 16. Said bottom portion of the body member 13 is also extended forwardly from the forward end of the fold 17 to provide a supporting finger 18 which extends forwardly from the front wall 15 and a restricted guide extension 19 which extends from the forward end of the finger 18, the upper edge of which is downwardly offset with respect to the upper edge of said finger 18. The lower ends of the front and rear walls 15 and 16 are provided with downwardly opening notches 29, as seen in Figures 4 and 6. The wall 14 is provided near its upper edge and adjacent the front wall 15 with two spaced openings 21. The folded portion 17 intermediate of the front and rear walls 15 and 16 is provided with a downwardly opening notch 22.

An elongated depth finding bar 23 is pivotally connected adjacent one end thereof by a fastening 24 to the forward end of the finger 18 and has a relatively narrow shorter end 25 extending forwardly from the pivot 24 and which terminates adjacent the outer end of the guide 19. The terminal of the restricted end 25 is provided with an upwardly projecting enlargement forming an upwardly converging pin engaging point 26. The depth finder bar 23 is mounted on the backside of the body portion 13 or the side thereof opposite to the side from which the The opposite end of the depth finder bar 23 extends to beyond the rear end of the folded portion 1'7 and has one end of a link 27 pivotally connected thereto at 28.

A disk 29 is pivoally supported at its center for rotation about a fastening 30 which is secured to the side wall 14 near its upper edge and adjacent the rear wall tween the side wall 14 and disk 29 so that said disk is spaced outwardly with respect to the depth finder bar 23. Accordingly, the lower portion of the disk 29 which overlaps a part of the bar 23 is capable of rotating relatively thereto. The opposite end of the: link 27 is connected by a pivot pin 32 to the disk 29 at a point spaced from its axis 3% A portion of the disk 29 is bent inwardly to provide a stop 33 which engages the link 27 to limit rotation of the disk 29 in one direction. The side of the disk 29 located adjacent the side wall 14 is inscribed with graduation lines 2% which converge inwardly fro-m a portion of the periphery thereof and which are preferably numbered consecutively in a clockwise direction from 1 to 5, as seen in Figure 1. A bent wire spring 34 has one end extending through the two openings 21 and is anchored adjustably thereby to the side wall 14. Said spring 3 2 1 extends from its anchored end down the outer side of the side wall 14 and downwardly across the outer sides of the finger 18 and depth finder bar 23 and is secured at its opposite end in an opening 35 of the bar 23, which opening is disposed so that said last mentioned end of the spring may move into the notch 22. The last mentioned spring end 35 exerts a downward pull on the longer end of the depth finder bar 23 to cause said bar to rock clockwise about the pivot 24 as seen in Figure 1 and so that the link 27 exerts a downward pull on the disk 29 to cause said disk to turn clockwise as seen in Figure 1 until rotational movement thereof is stopped by the disk stop 33 engaging the link 27. The disk 29 thus functions as a movable gauge part and the upper edge 35a of the side wall 14 functions with the graduation lines 29a of the disk 29 as a gauge line or point.

The parts previously described combine to form a lock decoder capable of being readily used by a locksmith for decoding locks. However, the lock decoder 12 additionally includes other means enabling it to be readily used by an inexperienced person in accurately decoding a lock. These additional parts include an elongated spacing bar 36 which is slidably disposed against the inner side of the side wall 14 and which extends slidably through and is guided by the slots 20. A bottom edge of the spacing bar 36 rests slidably upon the upper edge of the fold 17 and is supported thereby in the notches 21 A forward end 37 of the spacing bar 36 is laterally offset to be disposed slidably above the upper edge of the finger 18 and terminates in a restricted extension 38 which forms an extension of its bottom edge. The opposite end of the spacing bar 36 is provided with a laterally turn portion forming a handle 39 which is located beyond and rearwardly of the rear Wall 16. The upper edge of an intermediate portion of the spacing bar 36 which is located between the walls and 16 and is provided with a series of spaced notches 40 which are preferably consecutively numbered on the exposed side of the bar 36 and beneath said notches from 1 to 6. A spring strip 41 is disposed between the walls 15 and 16 and has its ends seating in recesses 42 of said walls, as best illustrated in Figure 6. The end portions of the spring 41 are inclined downwardly slightly from their seated ends and are connected at their adjacent ends by an arcuate downwardly extending intermediate portion 43 which selectively engages the notches 40. An elongated block 44 forming a handle by means of which the decoder 12 can be manually supported is disposed between the walls 15 and 16, adjacent their upper ends, and is detachably fastened thereto by fastenings 45.

A portion of a conventional type of revolving core or plug lock, designated generally 46, is illustrated in Figure 1, including a plug or core 47 which is turnably disposed in a lock case or barrel 43. The plug 47 is shown provided with the usual key slot 49 and with the usual set of pins 50 of different lengths which are slidably disposed radially in the plug 47 and which has inner ends extending into the key slot 49 and outer ends engaging against the bore of the barrel or cylinder 48 when the lock is unlocked, so that the plug pins 50 are out of alignment with the tumbler pins, not shown, of the cylinder 48 and which spring pressed tumbler pins, in one position of the plug 47, align with the plug pins 50 and are spring projected into the bores 51 of said pins 50 for displacing the pins 50 further into the key slot 49 to thus lock the plug against rotation in the cylinder. This conventional form of lock is illustrated in the patent to Abrams $1 2,087,423 wherein the plug or core is shown locked in Figure 4 by the tumbler pins of the barrel or cylinder. However, before the decoder 12 is used the lock 46 is unlocked. This can usually be accomplished by raking the pins 50 with a pick, not shown, so that the outer ends of the pins 50 will be disposed at the shear line 52 of the look, as illustrated in Figure 1, and so that the core 47 can then be turned to t the pins 50 out of alignment with the tumbler pins of the cylinder 48. The lock core or plug 47 may be turned either to the right or left to its unlocked position depending upon the type of lock being picked. Other locks are more diflicult to pick and require the use of a shim which is inserted between the plug and cylinder along the shear line 52 as each pin is picked.

Assuming that the lock has been picked and is in its unlocked position as illustrated in Figure l, the spacing bar 36 is fully retracted so that the spring portion 43 engages the left hand number 1 notch 41). The disk 29 is then turned counterclockwise as seen in Figure 1 so that the link 27 will lift the rear end of the depth finder bar 23 to displace the point 26 thereof downwardly to its position of Figure 8, approximately at the level of the upper edge of the guide 19. With the parts thus disposed, the guide 19 and the depth finder portions 25, 26 are inserted into the key slot 49 until the extension 38 strikes the outer end of the plug. The outer end of the extension is so spaced relatively to the point 26 when the spring portion 43 engages notch number 1 that the point 26 will be directly beneath the innermost pin 50. The decoder 12 is held by the handle 44 and the disk 29 is then released to permit the spring 34 to exert a downward pull on the rear end of the depth finder 23, causing said depth finder to pivot at 24 to elevate the point 26 thereof into engagement with the innermost pin 50. This clockwise swinging movement of the depth finder 23 as illustrated in Figure 1, will cause the link 27 to exert a downward pull on the disk 29 to rotate said disk clockwise until rotational movement thereof is stopped by the point 26 engaging the innermost pin to prevent further clockwise rocking movement of the depth finder 23. The disk 29 will then be disposed with one of the lines 29a aligned with the upper edge or gauge line 35 of the side wall 14 to thus give the code reading for the first pin 50. The disk 29 is then swung counterclockwise to return the point 26 to its position of Figure 8 and the spacing bar 36 is displaced by its handle 39 from right to left of Figure 1 to engage the spring portion 43 in the notch number 2. This will displace the extension 38 forwardly of the point 26 so that said point and the guide 19 will be retracted outwardly of the key slot 49 sufficiently to position the point 26 directly beneath the next to the innermost pin 50. The operation as previously described is then repeated for obtaining the reading of this pin and each successive pin. Most locks are provided with five pins 50 but occasionally a lock is provided with six pins and for this reason the bar 36 is provided with six notches 40, the right hand one of which is ordinarily not used and could obviously be provided with more notches for utilizing the decoder 12 with locks having more than six pins or tumblers. From the foregoing it will be readily apparent that one having no locksmith experience and skill may readily decode a lock with the decoder 12.

For locksmiths or those more skilled in the work, the spacing bar 36 need not be used and the point 26 and guide 19 may be slowly retracted from a fully inserted position in the slot 49 and the reading of the pins obtained as the disk 29 turns clockwise and counterclockwise to give the correct reading of each pin beneath which the point 26 comes to rest by upward swinging movement of the point under the biasing action of the spring 34.

Figures 9, 10 and 11 illustrate a slightly different form of the lock decoder, designated generally 53, including a body portion 13a having a side wall 14a, front wall 15a, rear wall 16a, a bottom folded portion 17a, a finger 18a and a guide 19a, all of which parts except the side wall 14a correspond to the parts of the body portion 13 of the decoder 12. The side wall 14a differs from the side wall 14 in that it is provided with an integral upwardly projecting extension forming a stationary dial 54 having a series of graduation lines 55 converging downwardly and to the right from an arcuate upper edge 56 thereof on. an inner side of said dial 54 and which are numbered 'consecutivelyfrom 1 to 5 in a counterclockwisedirectionwThe outer side of the dial 54, as

illustrated in Figure 10, is providedwith similar gradua- -tions 57 which are similarly numberedexceptin a clockwise direction and said graduations 57 are ofiset slightly fromthe graduations 55 for a purpose that will hereinafter become apparent.

In lieu of the-disk 29, a lever 58 is disposed on the i outer side of the wall 14a and is swingably supported ad t i jacent one enclthereof on a pivot 30a, corresponding to the pivot 30. The lever 58 has a free end portion which i is bent over and loosely engages around the arcuate dial edge 56 and which'terminates ina pointer 59 which is t i disposed on the inner side of the dial for movement over 5.

the graduation lines 55 and-to assume positions in front of dilferent of saidlines 55 toindicate readings obtained in the use of the decoder 53. Similarly, a straight edge 26auntil-itstrikes the pin beneath which it is disposed and to cause the lever-pointer toswing toward the stop 33a until swinging movement of the link 27a is interh i rupted by engagement of the point 26a with the pin, at

60 of the lever 58 "functions with the graduations 57 so u that the same reading can'be obtained from the outer side of the decoder 53 and as said straight edge 60 is offset slightly from the tip of the pointer 59, the graduation lines 57 are staggered slightly relatively to the graduation lines 55so that when the pointer 59 aligns with tively. A link 27a, corresponding to the link 27, is pivotally mounted at one end at 28a to the rear end of the bar 23a and is pivotally connected at its opposite end at 32a to the lever 58 at a point spaced from the pivot 30a of said lever. A curved spring wire 34a is anchored to the Wall 14a in opening 21a thereof, in the same manner.

that one end of the spring 34 is anchored in the openings 21. However, the opposite end of the spring 34a which is disposed across the outer side of the body portion 13a, is connected at 61 to the link 27a, intermediate of the ends of said link, to urge the link to swing down- Wardly about its pivot 32a.

A spacing bar 36a, corresponding to the spacing bar 36 and mounted in the same manner, slidably engages on the upper edge of the fold 17a and extends slidably through the downwardly opening notches a of the walls 15a and 16a. The upper edge of the intermediate portion of the spacing bar 36a is provided with notches 40a corresponding to the notches 40 and numbered consecutively from left to right from 1 to 5." However, a greater number of notches 40a may be provided if desired. A spring 41a, similar to the spring 41, is mounted in the same manner in recesses 42a of the walls 15a and 16a and has a downwardly oifset intermediate portion terminating in a rounded bottom 43a which selectively engages the notches 40a. The edge of the dial 54 located above the rear wall 16a is provided with an inturned portion forming a stop 33a to limit clockwise swinging movement of the lever-pointer 58 and downward swinging movement of the link 27a and of the rear end of the depth finder bar 23a. The decoder 53 is also provided with a handle 44a corresponding to the handle 44.

The operation of the decoder 53 is substantially identical to the operation of the decoder 12 as previously described in detail and a detailed description of its operation is therefore considered unnecessary. However it might be stated that the lever and pointer 58, 59 is swung away from the stop 33:: to displace the point 26a downwardly to approximately the level of the upper edge of the guide 19a for inserting the guide and point 26a into the key slot of a lock corresponding to the lock 46. With the point 26a selectively positioned by the spacing bar 36a beneath each plug pin, the spring 34a will. urge the link 27a to swing downwardly to elevate the point which'time the pointer 59 willbe disposed inalignment -with one of the graduations 55 and 'thewedge 60 in alignment with one of the graduations 57 to obtain the code reading of the pin engaged by the point 26a. This operation is repeated for each pin of thelock in conjunction with the operation of the spacing bar 36a, 'as previously described in detail inreference to the decoder 12.

Various other modifications andchanges are contemplated and may obviously be resorted to, without departing from the spirit or scope of theinventionas-hereinafter-defined by the appended claims.

I claim as my invention:

1. In a lock tumbler decoder, amainsupporting plate having laterally projected handle flanges along both sides and a reversely bent lower lip along itsbottom edge, which projects forwardly beyond one handle (flange and terminates in a lock key slot receiving guide to bear along its lower edge with the base of the key slot opposite the lock tumblers, a slide bar slidablysupported on the upper edge of said reversely bent lip and guided within aligned slots in both handle flanges, a lock face locating abutment on the end of theslide barnear said key slot receiving guide, a leaf spring bridging the space between and having its opposite ends supported by said handleflanges and -carrying an intermediate keeper detent for selective spaced locating seats in the slide bar, a rock lever pivotal- 'springlatching engagement with any one of a series of ly mounted on and in side by side relation with said key slot receiving guide and terminating in a tumbler contact seat to extend into the key slot and co-operate with the guide in gauging depth of successive tumblers in accord ance with detent latch position of said slide bar, and a movable indicator mounted on the plate and spaced from the rock lever pivot mounting and operatively connected with the rock lever for travel relative to said main supporting plate in giving a reading of tumbler seat relation to said guide lower edge.

2. In a lock tumbler decoder assembly, a pair of key slot receiving prongs for engagement respectively with the end of a tumbler and the side of a key slot opposite the tumbler, a pivot pin interconnecting said prongs and mounting one upon the other, a supporting plate body fixedly locating one of said prongs and having a pair of laterally disposed handle ears spaced apart in a direction axially of the key slot, a lock face engaging locator bar slidably guided in axially aligned slots in said handle ears for relative movement in a path parallel to the longitudinal extent of said fixedly located prong, a spring arm detent carried by the plate body to latch selectively with seats carried by said handle ear guided slidable locator bar, a movable indicator carried by the plate body for co-operation with a gauge marking presented on the plate body, and a motion transmitting connection between the movable indicator and the prong which is pinned to the fixedly located prong.

3. In a hand tool for finding lock tumbler depth, a supporting plate having a pair of longitudinally spaced apart laterally projecting ears with longitudinally aligned notches in laterally extended edges of the ears and immediately beside the plate, a plate extension overlying said edge notches for cooperation therewith in completing a slide guideway, a lock face engaging locator slidably mounted in said guideway, a resilient keeper between the locator and the support plate, a key slot receiving prong fixedly carried by the supporting plate, a lever having a key slot receiving feeler at one end and being pivotally connected to said prong at a point ahead of said supporting plate, and means whereby the opposite end of the lever cooperates with a plate carried gauge marker for a reading of the depth of a tumbler selected by the slide locator position set by said keeper.

4. In a lock decoder of the type wherein a pair of key slot receiving prongs are interpivoted for relative swinging in an arc whose angle of swing during a decoding operation gauges tumbler length from the shear line of the lock assembly, the improvement comprising a supporting plate with which one of the prongs is fixed and the swing of the other prong cooperates to give a reading, a pair of longitudinally spaced flanges projected laterally from said supporting plate as finger grip surfaces, a slide bar slidably mounted in longitudinally aligned slots in said spaced flanges for adjustment in a path parallel to said fixed prong and terminating in a lock face engaging locator abutment and a releasable adjustment retaining keeper between the slide bar and the supporting plate including a spring pressed detent carried by one thereof and a group of spaced detent seats carried by the other for selective engagement by said detent.

5. A universal tool for use with tumbler type key operated locks which differ from one another as to tumbler spacing and for finding tumbler depth between the side of the key slot opposite the tumblers and the shear line when the lock parts are in unlocked condition, comprising a hand manipulated support having a fixed projection insertable within the key slot to rest on the key slot side opposite the tumblers, a movable key slot receiving and tumbler engaging projection carried by the support for cooperation with the fixed projection in gauging tumbler depth, a series of interchangeable lock face engaging locators selectively detachably and shiftably mountable on the support, each locator having a group of position setting detent seats spaced apart difierently in different locators according to tumbler spacing of the lock for which each locator is usable, and a spring actuated detent carried by the support for releasable latching engagement with positioning seats of any locator selectively mounted in the support.

6. In a decoder for universal use with key operated locks of the pin tumbler type and which locks may difler from one another in the relative axial spacing of the tumblersfrom the lock face, a pair of interpivoted key slot receiving projections for engagement, respectively, with the side of a key slot opposite the tumblers and with individual tumblers selectively, thereby to gauge tumbler depth to the shear line of a previously picked lock, a support for said projections, a series of interchangeable lock face engaging locator bars, each having a series of spaced stop abutments whose spacing conforms respectively to plunger spacing of particular locks, a guide retainer on said support for detachably and slidably mounting a selected locator bar and a releasable keeper carried by the support for engagement selectively with locator bar stop abutments.

References Cited in the file of this patent UNITED STATES PATENTS Abrams July 20, 1947 1a.; La 1 1 

